1. Field of the Invention
The present invention relates generally to a thermal module, and more particularly to a thermal module having both a large-area heat transfer effect and a remote end heat transfer effect.
2. Description of the Related Art
There is a trend to develop thinner and thinner electronic apparatuses nowadays. The ultra-thin electronic apparatus includes miniaturized components. The heat generated by the miniaturized components of the electronic apparatus has become a major obstacle to having better performance of the electronic apparatus and system. Even if the semiconductors forming the electronic component have been more and more miniaturized, the electronic apparatus is still required to have high performance.
The miniaturization of the semiconductors will lead to increase of thermal flux. The challenge to cooling the product due to increase of thermal flux exceeds the challenge simply caused by increase of total heat. This is because the increase of thermal flux will lead to overheating at different times with respect to different sizes and may cause malfunction or even burnout of the electronic apparatus.
In order to solve the problem of narrow heat dissipation space of the conventional technique, a vapor chamber (VC) is generally positioned on the chip as a heat dissipation device (structure). In order to increase the capillarity limit of the vapor chamber, capillary structures with voids, such as copper posts, sintered coatings, sintered posts and foamed posts, are disposed in the vapor chamber as support structures and backflow passages. The micro-vapor chamber has very thin upper and lower walls (thickness under 1.5 mm). The support structures are connected between the upper and lower walls to avoid thermal expansion and malfunction.
The conventional vapor chamber serves to face-to-face uniformly transfer heat. Generally, the heat is uniformly transferred from a heat absorption face in contact with a heat source to a condensation face opposite to the heat absorption face. The vapor chamber is advantageous in that it has larger heat transfer area and is able to quickly and uniformly transfer the heat. However, the vapor chamber has a critical shortcoming that it can hardly transfer the heat to a remote end to dissipate the heat. In the case that the heat is not dissipated in time, the heat will accumulate around the heat source.
There is a conventional heat dissipation structure composed of heat pipe and vapor chamber. The outer sides of the heat pipe and the vapor chamber are welded with each other. The welding sections may cause thermal resistance. Moreover, the working fluid is filled in the vapor chamber to perform vapor-liquid circulation between the evaporation section and the condensation section. The heat is first transferred through the vapor chamber and then to the heat pipe welded with the vapor chamber. Therefore, the heat transfer effect is limited.